To estimate HIV incidence and explore evidence for changing sexual behaviour over time among men and women belonging to different socioeconomic groups in rural South Africa.
A cohort study conducted ...between 2001 and 2004; 3881 individuals aged 14-35 years enumerated in eight villages were eligible. At least three household visits were made to contact each eligible respondent at both timepoints. Sexual behaviour data were collected in structured, respondent-focused interviews. HIV serostatus was assessed using an oral fluid enzyme-linked immunosorbent assay at each timepoint.
Data on sexual behaviour were available from 1967 individuals at both timepoints. A total of 1286 HIV-negative individuals at baseline contributed to the analysis of incidence. HIV incidence was 2.2/100 person-years among men and 4.9/100 person-years in women, among whom it was highest in the least educated group. Median age at first sex was lower among later birth cohorts. A higher number of previously sexually active individuals reported having multiple partners in the past year in 2004 than 2001. Condom use with non-spousal partners increased from 2001 to 2004. Migrant men more often reported multiple partners. Migrant and more educated individuals of both sexes and women from wealthier households reported higher levels of condom use.
HIV incidence is high in rural South Africa, particularly among women of low education. Some risky sexual behaviours (early sexual debut, having multiple sexual partners) are becoming more common over time. Condom use is increasing. Existing HIV prevention strategies have only been partly effective in generating population-level behavioural change.
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•O‒O bond remains intact in all selective H2O2 production processes.•Coating is a common strategy to suppress metal leaching and sintering.•NH3 synthesis is possible via Mars-van ...Krevelen mechanism of nitrides.•Electrides and hydrides are new classes of NH3 synthesis catalysts.•Very limited cross-fertilization of knowledge among processes.
There is an urgent need to provide adequate and sustainable supplies of water and food to satisfy the demand of an increasing population. Catalysis plays important roles in meeting these needs by facilitating the synthesis of hydrogen peroxide that is used in water decontamination and chemicals production, and ammonia that is used as fertilizer. However, these chemicals are currently produced with processes that are either very energy-intensive or environmentally unfriendly. This article offers the perspectives of the challenges and opportunities in the production of these chemicals, focusing on the roles of catalysis in more sustainable, alternative production methods that minimize energy consumption and environmental impact. While not intended to be a comprehensive review, the article provides a critical review of selected literature relevant to its objectives, discusses areas needed for further research, and potential new directions inspired by new developments in related fields. For each chemical, production by thermal, electro-, and photo-excited processes are discussed. Problems that are common to these approaches and their differences are identified and possible solutions suggested.
This study discusses how much of the biases in top-of-atmosphere (TOA) radiation and clouds can be removed by parameter tuning in the present-day simulation of a climate model in the Coupled Model ...Inter-comparison Project phase 5 (CMIP5) generation. We used output of a perturbed parameter ensemble (PPE) experiment conducted with an atmosphere–ocean general circulation model (AOGCM) without flux adjustment. The Model for Interdisciplinary Research on Climate version 5 (MIROC5) was used for the PPE experiment. Output of the PPE was compared with satellite observation data to evaluate the model biases and the parametric uncertainty of the biases with respect to TOA radiation and clouds. The results indicate that removing or changing the sign of the biases by parameter tuning alone is difficult. In particular, the cooling bias of the shortwave cloud radiative effect at low latitudes could not be removed, neither in the zonal mean nor at each latitude–longitude grid point. The bias was related to the overestimation of both cloud amount and cloud optical thickness, which could not be removed by the parameter tuning either. However, they could be alleviated by tuning parameters such as the maximum cumulus updraft velocity at the cloud base. On the other hand, the bias of the shortwave cloud radiative effect in the Arctic was sensitive to parameter tuning. It could be removed by tuning such parameters as albedo of ice and snow both in the zonal mean and at each grid point. The obtained results illustrate the benefit of PPE experiments which provide useful information regarding effectiveness and limitations of parameter tuning. Implementing a shallow convection parameterization is suggested as a potential measure to alleviate the biases in radiation and clouds.
Henriksson et al. (2010), hereafter HALTL10, criticize Annan and Hargreaves (2006a) (AH06) primarily on the grounds that we assumed that different sources of data were conditionally independent given ...the climate sensitivity. While we consider this approximation to have been a reasonable one under the circumstances (and provided arguments to justify this approach), we also acknowledged its importance in our original paper and performed several sensitivity analyses. The alternative calculations presented by HALTL10 appear to strengthen rather than contradict our conclusion. HALTL10 additionally criticize Annan and Hargreaves (2009) (AH09) for proposing a Cauchy type prior (as an alternative to the use of a uniform prior, which was widespread up to that time) "without sufficient support", and further claim that anticipated economic damages were used as a means of selecting the prior. We are surprised by these claims, especially considering that the proposed prior was justified at some length both on the basis of both the "Charney report" (National Research Council, 1979) and basic physical arguments, and also in light of our elementary demonstration of the pathological failings of the most commonly-used alternative. Thus, these claims are factually incorrect.
The mid-PlioceneWarm Period (mPWP) is the most recent interval in which atmospheric carbon dioxide was substantially higher than in modern pre-industrial times. It is, therefore, a potentially ...valuable target for testing the ability of climate models to simulate climates warmer than the pre-industrial state. The recent Pliocene model inter-comparison Project (PlioMIP) presented boundary conditions for the mPWP, and a protocol for climate model experiments. Here we analyse results from the PlioMIP and, for the first time, discuss the potential for this interval to usefully constrain the equilibrium climate sensitivity. We present an estimate of 1.8-3.6 °C, but there are considerable uncertainties surrounding the analysis. We consider the extent to which these uncertainties may be lessened in the next few years.
1-(5-{(2R,3S)-2-({(1R)-1-3,5-Bis(trifluoromethyl)phenylethyl}oxy)-3-(4-fluorophenyl)morpholin-4-ylmethyl}-2H-1,2,3-triazol-4-yl)-N, N-dimethylmethanamine hydrochloride 3 is a high affinity, orally ...active, h-NK1 receptor antagonist with a long central duration of action and a solubility in water of >100 mg/mL. The construction of the 5-dimethylaminomethyl 1,2,3-triazol-4-yl unit, which incorporates the solubilizing group of 3, was accomplished by thermal rearrangement of a propargylic azide in the presence of dimethylamine. Compound 3 is highly effective in pre-clinical tests that are relevant to clinical efficacy in emesis and depression.
The auroral absorption spike event, occurring generally at the onset of a substorm, is distinguished by its high intensity and short duration. This paper reports the presence of a fine structure ...within the spike event. Analysis of selected examples using the Morlet wavelet shows that within the 1 – 2 min duration of the spike are significant modulations with periodicities in the bands 15 – 60 s (67 – 16 mHz), and 5 – 10 s (200 – 100 mHz), the former being the stronger. The slower fluctuations can amount to more than 10% of the absorption, and they were observed in every example (seven out of nine) in which the spike was moving poleward. They were absent in the other two cases, when the spike moved equatorward. In the examples studied, the 15 – 60 s absorption pulsations were accompanied by magnetic micropulsations of impulsive type (Pi) having a periodity that was similar or harmonically related. The connection is only close while the spike event is moving. Consideration of the details suggests that both the magnetic and the absorption pulsations are related to the acceleration process at substorm onset, the flux of energetic particles into the auroral zone producing the radio absorption being modulated with, though not by, the geomagnetic field variations. The 5 – 10 s pulsations, which are considerably weaker, appeared in both the absorption and the magnetic records, but in this case with no obvious connection between them.
Objective Assess the cost-effectiveness of an intervention combining microfinance with gender and HIV training for the prevention of intimate partner violence (IPV) in South Africa. Methods We ...performed a cost-effectiveness analysis alongside a cluster-randomized trial. We assessed the cost-effectiveness of the intervention in both the trial and initial scale-up phase. Results We estimated the cost per DALY gained as US$7688 for the trial phase and US$2307 for the initial scale-up. The findings were sensitive to the statistical uncertainty in effect estimates but otherwise robust to other key assumptions employed in the analysis. Conclusions The findings suggest that this combined economic and health intervention was cost-effective in its trial phase and highly cost-effective in scale-up. These estimates are probably conservative, as they do not include the health and development benefits of the intervention beyond IPV reduction.
Proposals to use red mud, the waste produced by the extraction of alumina from bauxite ore in the Bayer process, as a material for treatment of heavy metal-contaminated water are limited by its ...inherent alkalinity and variability. Attempts to lower its pH have been largely unreliable. However, an alternative strategy is carbonisation of red mud by catalytic hydrocarbon cracking, which results in a magnetic material of greater surface area. The efficacy of this material has been compared with that of the untreated parent red mud and acidified red mud for the sorption of CrO42−, Cu2+ and Pb2+. Carbonised red mud does not remove CrO42− from solution, but shows enhancement of Cu2+ and Pb2+ removal. There is an approximate ten-fold increase in removal of Cu2+ and Pb2+ by carbonised red mud compared with acidified red mud.
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► Carbonised red mud is a novel material. ► It is produced when red mud is used as a catalyst for methane cracking. ► It has potential as a treatment to remove heavy metals from contaminated water. ► It is magnetic, allowing easy separation of metal-loaded material.
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